s there any way to get Ps to respond so I can resume working and save ?
I would not be optimistic in that regard.
In any case you have omitted to give potentially relevant data like OS, hardware, …
Are Photoshop and OS fully updated and have you performed the usual trouble-shooting routines (trashing prefs by keeping command-alt-shift/ctrl-alt-shift pressed while starting Photoshop after making sure all customized presets like Actions, Patterns, Brushes etc. have been saved and making a note of the Preferences you’ve changed, 3rd party plug-ins deactivation, system maintenance, cleaning caches, font validation, etc.)?
It's no consolation to you now I'm sure, but Photoshop CS6 has the new Auto-Save feature, and it would likely have functioned in this case to recover a recent copy of your file after you killed the hung process and restarted Photoshop.